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<div class="fragment"><pre class="fragment"><a name="l00001"></a>00001 <span class="comment">/*</span>
<a name="l00002"></a>00002 <span class="comment"> * Copyright (c) 2010-2011, NVIDIA Corporation</span>
<a name="l00003"></a>00003 <span class="comment"> * All rights reserved.</span>
<a name="l00004"></a>00004 <span class="comment"> *</span>
<a name="l00005"></a>00005 <span class="comment"> * Redistribution and use in source and binary forms, with or without</span>
<a name="l00006"></a>00006 <span class="comment"> * modification, are permitted provided that the following conditions are met:</span>
<a name="l00007"></a>00007 <span class="comment"> *   * Redistributions of source code must retain the above copyright</span>
<a name="l00008"></a>00008 <span class="comment"> *     notice, this list of conditions and the following disclaimer.</span>
<a name="l00009"></a>00009 <span class="comment"> *   * Redistributions in binary form must reproduce the above copyright</span>
<a name="l00010"></a>00010 <span class="comment"> *     notice, this list of conditions and the following disclaimer in the</span>
<a name="l00011"></a>00011 <span class="comment"> *     documentation and/or other materials provided with the distribution.</span>
<a name="l00012"></a>00012 <span class="comment"> *   * Neither the name of NVIDIA Corporation nor the</span>
<a name="l00013"></a>00013 <span class="comment"> *     names of its contributors may be used to endorse or promote products</span>
<a name="l00014"></a>00014 <span class="comment"> *     derived from this software without specific prior written permission.</span>
<a name="l00015"></a>00015 <span class="comment"> *</span>
<a name="l00016"></a>00016 <span class="comment"> * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS &quot;AS IS&quot; AND</span>
<a name="l00017"></a>00017 <span class="comment"> * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED</span>
<a name="l00018"></a>00018 <span class="comment"> * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE</span>
<a name="l00019"></a>00019 <span class="comment"> * DISCLAIMED. IN NO EVENT SHALL &lt;COPYRIGHT HOLDER&gt; BE LIABLE FOR ANY</span>
<a name="l00020"></a>00020 <span class="comment"> * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES</span>
<a name="l00021"></a>00021 <span class="comment"> * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;</span>
<a name="l00022"></a>00022 <span class="comment"> * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND</span>
<a name="l00023"></a>00023 <span class="comment"> * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT</span>
<a name="l00024"></a>00024 <span class="comment"> * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS</span>
<a name="l00025"></a>00025 <span class="comment"> * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.</span>
<a name="l00026"></a>00026 <span class="comment"> */</span>
<a name="l00027"></a>00027 
<a name="l00028"></a>00028 <span class="keyword">namespace </span>nih {
<a name="l00029"></a>00029 
<a name="l00030"></a>00030 <span class="comment">// get a set of 2d stratified samples</span>
<a name="l00031"></a>00031 <span class="keyword">template</span> &lt;<span class="keyword">typename</span> T&gt;
<a name="l00032"></a><a class="code" href="structnih_1_1_m_j_sampler.html#a7efa9e4be3bfab3bbeb2c0e1d293f608">00032</a> <span class="keywordtype">void</span> <a class="code" href="structnih_1_1_m_j_sampler.html#a7efa9e4be3bfab3bbeb2c0e1d293f608">MJSampler::sample</a>(
<a name="l00033"></a>00033         <span class="keyword">const</span> uint32    samples_x,
<a name="l00034"></a>00034         <span class="keyword">const</span> uint32    samples_y,
<a name="l00035"></a>00035         <a class="code" href="structnih_1_1_vector_3_01_t_00_012_01_4.html">Vector&lt;T,2&gt;</a>*    samples,
<a name="l00036"></a>00036         Ordering                ordering)
<a name="l00037"></a>00037 {
<a name="l00038"></a>00038         m_sample_xy.resize( samples_x * samples_y );
<a name="l00039"></a>00039         <span class="keywordflow">for</span> (uint32 y = 0; y &lt; samples_y; y++)
<a name="l00040"></a>00040         {
<a name="l00041"></a>00041                 <span class="keywordflow">for</span> (uint32 x = 0; x &lt; samples_x; x++)
<a name="l00042"></a>00042                 {
<a name="l00043"></a>00043                         <span class="keyword">const</span> <span class="keywordtype">size_t</span> index = y * samples_x + x;
<a name="l00044"></a>00044                         m_sample_xy[index].x = y;
<a name="l00045"></a>00045                         m_sample_xy[index].y = x;
<a name="l00046"></a>00046                 }
<a name="l00047"></a>00047         }
<a name="l00048"></a>00048         <span class="keywordflow">for</span> (uint32 y = 0; y &lt; samples_y; y++)
<a name="l00049"></a>00049         {
<a name="l00050"></a>00050                 <span class="keywordflow">for</span> (uint32 x = 0; x &lt; samples_x-1; x++)
<a name="l00051"></a>00051                 {
<a name="l00052"></a>00052                         <span class="keyword">const</span> <span class="keywordtype">float</span> r = m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>();
<a name="l00053"></a>00053                         <span class="keyword">const</span> uint32 xx = <a class="code" href="group__vectors.html#ga5809911d15c32de18955c59865379695">std::min</a>( uint32(<span class="keywordtype">float</span>(r) * (samples_x - x)) + x, samples_x-1u );
<a name="l00054"></a>00054 
<a name="l00055"></a>00055                         <span class="keyword">const</span> <span class="keywordtype">size_t</span> index1 = y * samples_x + x;
<a name="l00056"></a>00056                         <span class="keyword">const</span> <span class="keywordtype">size_t</span> index2 = y * samples_x + xx;
<a name="l00057"></a>00057 
<a name="l00058"></a>00058                         std::swap( m_sample_xy[index1].y, m_sample_xy[index2].y );
<a name="l00059"></a>00059                 }
<a name="l00060"></a>00060         }
<a name="l00061"></a>00061         <span class="keywordflow">for</span> (uint32 x = 0; x &lt; samples_x; x++)
<a name="l00062"></a>00062         {
<a name="l00063"></a>00063                 <span class="keywordflow">for</span> (uint32 y = 0; y &lt; samples_y-1; y++)
<a name="l00064"></a>00064                 {
<a name="l00065"></a>00065                         <span class="keyword">const</span> <span class="keywordtype">float</span> r = m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>();
<a name="l00066"></a>00066                         <span class="keyword">const</span> uint32 yy = <a class="code" href="group__vectors.html#ga5809911d15c32de18955c59865379695">std::min</a>( uint32(<span class="keywordtype">float</span>(r) * (samples_y - y)) + y, samples_y-1u );
<a name="l00067"></a>00067 
<a name="l00068"></a>00068                         <span class="keyword">const</span> <span class="keywordtype">size_t</span> index1 = y * samples_x + x;
<a name="l00069"></a>00069                         <span class="keyword">const</span> <span class="keywordtype">size_t</span> index2 = yy * samples_x + x;
<a name="l00070"></a>00070 
<a name="l00071"></a>00071                         std::swap( m_sample_xy[index1].x, m_sample_xy[index2].x );
<a name="l00072"></a>00072                 }
<a name="l00073"></a>00073         }
<a name="l00074"></a>00074 
<a name="l00075"></a>00075         <span class="keyword">const</span> uint32 num_samples = samples_x * samples_y;
<a name="l00076"></a>00076         <span class="keyword">const</span> T inv = T(1.0) / T(num_samples);
<a name="l00077"></a>00077         <span class="keywordflow">for</span> (uint32 y = 0; y &lt; samples_y; y++)
<a name="l00078"></a>00078         {
<a name="l00079"></a>00079                 <span class="keywordflow">for</span> (uint32 x = 0; x &lt; samples_x; x++)
<a name="l00080"></a>00080                 {
<a name="l00081"></a>00081                         <span class="keyword">const</span> <span class="keywordtype">size_t</span> index = y * samples_x + x;
<a name="l00082"></a>00082                         samples[index][0] = (T(m_sample_xy[index].x + x * samples_y) + m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>()) * inv;
<a name="l00083"></a>00083                         samples[index][1] = (T(m_sample_xy[index].y + y * samples_x) + m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>()) * inv;
<a name="l00084"></a>00084                 }
<a name="l00085"></a>00085         }
<a name="l00086"></a>00086         <span class="keywordflow">if</span> (ordering == kRandom)
<a name="l00087"></a>00087         {
<a name="l00088"></a>00088                 <span class="keywordflow">for</span> (uint32 i = 0; i &lt; num_samples; i++)
<a name="l00089"></a>00089                 {
<a name="l00090"></a>00090                         <span class="keyword">const</span> <span class="keywordtype">float</span> r = m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>();
<a name="l00091"></a>00091                         <span class="keyword">const</span> uint32 j = <a class="code" href="group__vectors.html#ga5809911d15c32de18955c59865379695">std::min</a>( uint32(<span class="keywordtype">float</span>(r) * (num_samples - i)) + i, num_samples-1u );
<a name="l00092"></a>00092                         std::swap( samples[i], samples[j] );
<a name="l00093"></a>00093                 }
<a name="l00094"></a>00094         }
<a name="l00095"></a>00095 }
<a name="l00096"></a>00096 <span class="comment">// get a set of 3d stratified samples</span>
<a name="l00097"></a>00097 <span class="comment">// the first 2 dimensions are multi-jittered, the third one</span>
<a name="l00098"></a>00098 <span class="comment">// is selected with latin hypercube sampling wrt the first 2.</span>
<a name="l00099"></a>00099 <span class="keyword">template</span> &lt;<span class="keyword">typename</span> T&gt;
<a name="l00100"></a><a class="code" href="structnih_1_1_m_j_sampler.html#a162a0c19596eef3f9debe2ee0550c136">00100</a> <span class="keywordtype">void</span> <a class="code" href="structnih_1_1_m_j_sampler.html#a7efa9e4be3bfab3bbeb2c0e1d293f608">MJSampler::sample</a>(
<a name="l00101"></a>00101         <span class="keyword">const</span> uint32    samples_x,
<a name="l00102"></a>00102         <span class="keyword">const</span> uint32    samples_y,
<a name="l00103"></a>00103         <a class="code" href="structnih_1_1_vector_3_01_t_00_013_01_4.html">Vector&lt;T,3&gt;</a>*    samples)
<a name="l00104"></a>00104 {
<a name="l00105"></a>00105         m_sample_xy.resize( samples_x * samples_y );
<a name="l00106"></a>00106         <span class="keywordflow">for</span> (uint32 y = 0; y &lt; samples_y; y++)
<a name="l00107"></a>00107         {
<a name="l00108"></a>00108                 <span class="keywordflow">for</span> (uint32 x = 0; x &lt; samples_x; x++)
<a name="l00109"></a>00109                 {
<a name="l00110"></a>00110                         <span class="keyword">const</span> <span class="keywordtype">size_t</span> index = y * samples_x + x;
<a name="l00111"></a>00111                         m_sample_xy[index].x = y;
<a name="l00112"></a>00112                         m_sample_xy[index].y = x;
<a name="l00113"></a>00113                 }
<a name="l00114"></a>00114         }
<a name="l00115"></a>00115         <span class="keywordflow">for</span> (uint32 y = 0; y &lt; samples_y; y++)
<a name="l00116"></a>00116         {
<a name="l00117"></a>00117                 <span class="keywordflow">for</span> (uint32 x = 0; x &lt; samples_x-1; x++)
<a name="l00118"></a>00118                 {
<a name="l00119"></a>00119                         <span class="keyword">const</span> <span class="keywordtype">float</span> r = m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>();
<a name="l00120"></a>00120                         <span class="keyword">const</span> uint32 xx = <a class="code" href="group__vectors.html#ga5809911d15c32de18955c59865379695">std::min</a>( uint32(<span class="keywordtype">float</span>(r) * (samples_x - x)) + x, samples_x-1u );
<a name="l00121"></a>00121 
<a name="l00122"></a>00122                         <span class="keyword">const</span> <span class="keywordtype">size_t</span> index1 = y * samples_x + x;
<a name="l00123"></a>00123                         <span class="keyword">const</span> <span class="keywordtype">size_t</span> index2 = y * samples_x + xx;
<a name="l00124"></a>00124 
<a name="l00125"></a>00125                         std::swap( m_sample_xy[index1].y, m_sample_xy[index2].y );
<a name="l00126"></a>00126                 }
<a name="l00127"></a>00127         }
<a name="l00128"></a>00128         <span class="keywordflow">for</span> (uint32 x = 0; x &lt; samples_x; x++)
<a name="l00129"></a>00129         {
<a name="l00130"></a>00130                 <span class="keywordflow">for</span> (uint32 y = 0; y &lt; samples_y-1; y++)
<a name="l00131"></a>00131                 {
<a name="l00132"></a>00132                         <span class="keyword">const</span> <span class="keywordtype">float</span> r = m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>();
<a name="l00133"></a>00133                         <span class="keyword">const</span> uint32 yy = <a class="code" href="group__vectors.html#ga5809911d15c32de18955c59865379695">std::min</a>( uint32(<span class="keywordtype">float</span>(r) * (samples_y - y)) + y, samples_y-1u );
<a name="l00134"></a>00134 
<a name="l00135"></a>00135                         <span class="keyword">const</span> <span class="keywordtype">size_t</span> index1 = y * samples_x + x;
<a name="l00136"></a>00136                         <span class="keyword">const</span> <span class="keywordtype">size_t</span> index2 = yy * samples_x + x;
<a name="l00137"></a>00137 
<a name="l00138"></a>00138                         std::swap( m_sample_xy[index1].x, m_sample_xy[index2].x );
<a name="l00139"></a>00139                 }
<a name="l00140"></a>00140         }
<a name="l00141"></a>00141 
<a name="l00142"></a>00142         <span class="keyword">const</span> uint32 num_samples = samples_x * samples_y;
<a name="l00143"></a>00143         <span class="keyword">const</span> T inv = T(1.0) / T(num_samples);
<a name="l00144"></a>00144         <span class="keywordflow">for</span> (uint32 y = 0; y &lt; samples_y; y++)
<a name="l00145"></a>00145         {
<a name="l00146"></a>00146                 <span class="keywordflow">for</span> (uint32 x = 0; x &lt; samples_x; x++)
<a name="l00147"></a>00147                 {
<a name="l00148"></a>00148                         <span class="keyword">const</span> <span class="keywordtype">size_t</span> index = y * samples_x + x;
<a name="l00149"></a>00149                         samples[index][0] = (T(m_sample_xy[index].x + x * samples_y) + m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>()) * inv;
<a name="l00150"></a>00150                         samples[index][1] = (T(m_sample_xy[index].y + y * samples_x) + m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>()) * inv;
<a name="l00151"></a>00151                         samples[index][2] = (T(index) + m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>()) * inv;
<a name="l00152"></a>00152                 }
<a name="l00153"></a>00153         }
<a name="l00154"></a>00154         <span class="keywordflow">for</span> (uint32 i = 0; i &lt; num_samples; i++)
<a name="l00155"></a>00155         {
<a name="l00156"></a>00156                 <span class="keyword">const</span> <span class="keywordtype">float</span> r = m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>();
<a name="l00157"></a>00157                 <span class="keyword">const</span> uint32 j = <a class="code" href="group__vectors.html#ga5809911d15c32de18955c59865379695">std::min</a>( uint32(<span class="keywordtype">float</span>(r) * (num_samples - i)) + i, num_samples-1u );
<a name="l00158"></a>00158                 std::swap( samples[i], samples[j] );
<a name="l00159"></a>00159         }
<a name="l00160"></a>00160 }
<a name="l00161"></a>00161 <span class="comment">// get a set of 4d stratified samples</span>
<a name="l00162"></a>00162 <span class="keyword">template</span> &lt;<span class="keyword">typename</span> T&gt;
<a name="l00163"></a><a class="code" href="structnih_1_1_m_j_sampler.html#a4c2fc9b264a9f2de35125d51e4e19fe4">00163</a> <span class="keywordtype">void</span> <a class="code" href="structnih_1_1_m_j_sampler.html#a7efa9e4be3bfab3bbeb2c0e1d293f608">MJSampler::sample</a>(
<a name="l00164"></a>00164         <span class="keyword">const</span> uint32    samples_x,
<a name="l00165"></a>00165         <span class="keyword">const</span> uint32    samples_y,
<a name="l00166"></a>00166         <a class="code" href="structnih_1_1_vector_3_01_t_00_014_01_4.html">Vector&lt;T,4&gt;</a>*    samples,
<a name="l00167"></a>00167         Ordering                ordering)
<a name="l00168"></a>00168 {
<a name="l00169"></a>00169         <span class="keywordflow">for</span> (uint32 offset = 0; offset &lt;= 2; offset += 2)
<a name="l00170"></a>00170         {
<a name="l00171"></a>00171                 m_sample_xy.resize( samples_x * samples_y );
<a name="l00172"></a>00172                 <span class="keywordflow">for</span> (uint32 y = 0; y &lt; samples_y; y++)
<a name="l00173"></a>00173                 {
<a name="l00174"></a>00174                         <span class="keywordflow">for</span> (uint32 x = 0; x &lt; samples_x; x++)
<a name="l00175"></a>00175                         {
<a name="l00176"></a>00176                                 <span class="keyword">const</span> <span class="keywordtype">size_t</span> index = y * samples_x + x;
<a name="l00177"></a>00177                                 m_sample_xy[index].x = y;
<a name="l00178"></a>00178                                 m_sample_xy[index].y = x;
<a name="l00179"></a>00179                         }
<a name="l00180"></a>00180                 }
<a name="l00181"></a>00181                 <span class="keywordflow">for</span> (uint32 y = 0; y &lt; samples_y; y++)
<a name="l00182"></a>00182                 {
<a name="l00183"></a>00183                         <span class="keywordflow">for</span> (uint32 x = 0; x &lt; samples_x-1; x++)
<a name="l00184"></a>00184                         {
<a name="l00185"></a>00185                                 <span class="keyword">const</span> <span class="keywordtype">float</span> r = m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>();
<a name="l00186"></a>00186                                 <span class="keyword">const</span> uint32 xx = <a class="code" href="group__vectors.html#ga5809911d15c32de18955c59865379695">std::min</a>( uint32(<span class="keywordtype">float</span>(r) * (samples_x - x)) + x, samples_x-1u );
<a name="l00187"></a>00187 
<a name="l00188"></a>00188                                 <span class="keyword">const</span> <span class="keywordtype">size_t</span> index1 = y * samples_x + x;
<a name="l00189"></a>00189                                 <span class="keyword">const</span> <span class="keywordtype">size_t</span> index2 = y * samples_x + xx;
<a name="l00190"></a>00190 
<a name="l00191"></a>00191                                 std::swap( m_sample_xy[index1].y, m_sample_xy[index2].y );
<a name="l00192"></a>00192                         }
<a name="l00193"></a>00193                 }
<a name="l00194"></a>00194                 <span class="keywordflow">for</span> (uint32 x = 0; x &lt; samples_x; x++)
<a name="l00195"></a>00195                 {
<a name="l00196"></a>00196                         <span class="keywordflow">for</span> (uint32 y = 0; y &lt; samples_y-1; y++)
<a name="l00197"></a>00197                         {
<a name="l00198"></a>00198                                 <span class="keyword">const</span> <span class="keywordtype">float</span> r = m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>();
<a name="l00199"></a>00199                                 <span class="keyword">const</span> uint32 yy = <a class="code" href="group__vectors.html#ga5809911d15c32de18955c59865379695">std::min</a>( uint32(<span class="keywordtype">float</span>(r) * (samples_y - y)) + y, samples_y-1u );
<a name="l00200"></a>00200 
<a name="l00201"></a>00201                                 <span class="keyword">const</span> <span class="keywordtype">size_t</span> index1 = y * samples_x + x;
<a name="l00202"></a>00202                                 <span class="keyword">const</span> <span class="keywordtype">size_t</span> index2 = yy * samples_x + x;
<a name="l00203"></a>00203 
<a name="l00204"></a>00204                                 std::swap( m_sample_xy[index1].x, m_sample_xy[index2].x );
<a name="l00205"></a>00205                         }
<a name="l00206"></a>00206                 }
<a name="l00207"></a>00207 
<a name="l00208"></a>00208                 <span class="keyword">const</span> uint32 num_samples = samples_x * samples_y;
<a name="l00209"></a>00209                 <span class="keyword">const</span> T inv = T(1.0) / T(num_samples);
<a name="l00210"></a>00210                 <span class="keywordflow">for</span> (uint32 y = 0; y &lt; samples_y; y++)
<a name="l00211"></a>00211                 {
<a name="l00212"></a>00212                         <span class="keywordflow">for</span> (uint32 x = 0; x &lt; samples_x; x++)
<a name="l00213"></a>00213                         {
<a name="l00214"></a>00214                                 <span class="keyword">const</span> <span class="keywordtype">size_t</span> index = y * samples_x + x;
<a name="l00215"></a>00215                                 samples[index][offset+0] = (T(m_sample_xy[index].x + x * samples_y) + m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>()) * inv;
<a name="l00216"></a>00216                                 samples[index][offset+1] = (T(m_sample_xy[index].y + y * samples_x) + m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>()) * inv;
<a name="l00217"></a>00217                         }
<a name="l00218"></a>00218                 }
<a name="l00219"></a>00219                 <span class="keywordflow">if</span> (ordering == kRandom)
<a name="l00220"></a>00220                 {
<a name="l00221"></a>00221                         <span class="keyword">const</span> uint32 num_samples = samples_x * samples_y;
<a name="l00222"></a>00222                         <span class="keywordflow">for</span> (uint32 i = 0; i &lt; num_samples; i++)
<a name="l00223"></a>00223                         {
<a name="l00224"></a>00224                                 <span class="keyword">const</span> <span class="keywordtype">float</span> r = m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>();
<a name="l00225"></a>00225                                 <span class="keyword">const</span> uint32 j = <a class="code" href="group__vectors.html#ga5809911d15c32de18955c59865379695">std::min</a>( uint32(<span class="keywordtype">float</span>(r) * (num_samples - i)) + i, num_samples-1u );
<a name="l00226"></a>00226                                 std::swap( samples[i][offset+0], samples[j][offset+0] );
<a name="l00227"></a>00227                                 std::swap( samples[i][offset+1], samples[j][offset+1] );
<a name="l00228"></a>00228                         }
<a name="l00229"></a>00229                 }
<a name="l00230"></a>00230         }
<a name="l00231"></a>00231 }
<a name="l00232"></a>00232 
<a name="l00233"></a><a class="code" href="structnih_1_1_sampler.html#a393317f10a5ada969a41cf1f037bc900">00233</a> <span class="keyword">inline</span> <span class="keywordtype">void</span> <a class="code" href="structnih_1_1_sampler.html#a393317f10a5ada969a41cf1f037bc900">Sampler::sample</a>(
<a name="l00234"></a>00234         <span class="keyword">const</span> uint32    num_samples,
<a name="l00235"></a>00235         uint32*                 samples)
<a name="l00236"></a>00236 {
<a name="l00237"></a>00237         <span class="keywordflow">for</span> (uint32 i = 0; i &lt; num_samples; i++)
<a name="l00238"></a>00238                 samples[i] = i;
<a name="l00239"></a>00239 
<a name="l00240"></a>00240         <span class="keywordflow">for</span> (uint32 i = 0; i &lt; num_samples; i++)
<a name="l00241"></a>00241         {
<a name="l00242"></a>00242                 <span class="keyword">const</span> <span class="keywordtype">float</span> r = m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>();
<a name="l00243"></a>00243                 <span class="keyword">const</span> uint32 j = <a class="code" href="group__vectors.html#ga5809911d15c32de18955c59865379695">std::min</a>( uint32(<span class="keywordtype">float</span>(r) * (num_samples - i)) + i, num_samples-1u );
<a name="l00244"></a>00244                 std::swap( samples[i], samples[j] );
<a name="l00245"></a>00245         }
<a name="l00246"></a>00246 }
<a name="l00247"></a>00247 
<a name="l00248"></a>00248 <span class="comment">// get a set of 1d stratified samples</span>
<a name="l00249"></a>00249 <span class="keyword">template</span> &lt;<span class="keyword">typename</span> T&gt;
<a name="l00250"></a><a class="code" href="structnih_1_1_sampler.html#a24346176a69c4450e74f760d65b6c287">00250</a> <span class="keyword">inline</span> <span class="keywordtype">void</span> <a class="code" href="structnih_1_1_sampler.html#a393317f10a5ada969a41cf1f037bc900">Sampler::sample</a>(
<a name="l00251"></a>00251         <span class="keyword">const</span> uint32    num_samples,
<a name="l00252"></a>00252         T*                              samples)
<a name="l00253"></a>00253 {
<a name="l00254"></a>00254         m_sample_x.resize( num_samples );
<a name="l00255"></a>00255 
<a name="l00256"></a>00256         <span class="keywordflow">for</span> (uint32 i = 0; i &lt; num_samples; i++)
<a name="l00257"></a>00257                 m_sample_x[i] = i;
<a name="l00258"></a>00258 
<a name="l00259"></a>00259         <span class="keywordflow">for</span> (uint32 i = 0; i &lt; num_samples; i++)
<a name="l00260"></a>00260         {
<a name="l00261"></a>00261                 <span class="keyword">const</span> <span class="keywordtype">float</span> r = m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>();
<a name="l00262"></a>00262                 <span class="keyword">const</span> uint32 j = <a class="code" href="group__vectors.html#ga5809911d15c32de18955c59865379695">std::min</a>( uint32(<span class="keywordtype">float</span>(r) * (num_samples - i)) + i, num_samples-1u );
<a name="l00263"></a>00263                 std::swap( m_sample_x[i], m_sample_x[j] );
<a name="l00264"></a>00264         }
<a name="l00265"></a>00265         <span class="keyword">const</span> T inv = T(1.0) / T(num_samples);
<a name="l00266"></a>00266         <span class="keywordflow">for</span> (uint32 i = 0; i &lt; num_samples; i++)
<a name="l00267"></a>00267                 samples[i] = (T(m_sample_x[i]) + m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>()) * inv;
<a name="l00268"></a>00268 }
<a name="l00269"></a>00269 <span class="comment">// get a set of 2d stratified samples</span>
<a name="l00270"></a>00270 <span class="keyword">template</span> &lt;<span class="keyword">typename</span> T&gt;
<a name="l00271"></a><a class="code" href="structnih_1_1_sampler.html#a133bf443ccb7341c8faccecbdbafaa3e">00271</a> <span class="keyword">inline</span> <span class="keywordtype">void</span> <a class="code" href="structnih_1_1_sampler.html#a393317f10a5ada969a41cf1f037bc900">Sampler::sample</a>(
<a name="l00272"></a>00272         <span class="keyword">const</span> uint32    num_samples,
<a name="l00273"></a>00273         <a class="code" href="structnih_1_1_vector_3_01_t_00_012_01_4.html">Vector&lt;T,2&gt;</a>*    samples)
<a name="l00274"></a>00274 {
<a name="l00275"></a>00275         m_sample_x.resize( num_samples );
<a name="l00276"></a>00276         m_sample_y.resize( num_samples );
<a name="l00277"></a>00277 
<a name="l00278"></a>00278         <span class="keywordflow">for</span> (uint32 i = 0; i &lt; num_samples; i++)
<a name="l00279"></a>00279         {
<a name="l00280"></a>00280                 m_sample_x[i] = i;
<a name="l00281"></a>00281                 m_sample_y[i] = i;
<a name="l00282"></a>00282         }
<a name="l00283"></a>00283         <span class="keywordflow">for</span> (uint32 i = 0; i &lt; num_samples; i++)
<a name="l00284"></a>00284         {
<a name="l00285"></a>00285                 {
<a name="l00286"></a>00286                         <span class="keyword">const</span> <span class="keywordtype">float</span> r = m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>();
<a name="l00287"></a>00287                         <span class="keyword">const</span> uint32 j = <a class="code" href="group__vectors.html#ga5809911d15c32de18955c59865379695">std::min</a>( uint32(<span class="keywordtype">float</span>(r) * (num_samples - i)) + i, num_samples-1u );
<a name="l00288"></a>00288                         std::swap( m_sample_x[i], m_sample_x[j] );
<a name="l00289"></a>00289                 }
<a name="l00290"></a>00290                 {
<a name="l00291"></a>00291                         <span class="keyword">const</span> <span class="keywordtype">float</span> r = m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>();
<a name="l00292"></a>00292                         <span class="keyword">const</span> uint32 j = <a class="code" href="group__vectors.html#ga5809911d15c32de18955c59865379695">std::min</a>( uint32(<span class="keywordtype">float</span>(r) * (num_samples - i)) + i, num_samples-1u );
<a name="l00293"></a>00293                         std::swap( m_sample_y[i], m_sample_y[j] );
<a name="l00294"></a>00294                 }
<a name="l00295"></a>00295         }
<a name="l00296"></a>00296         <span class="keyword">const</span> T inv = T(1.0) / T(num_samples);
<a name="l00297"></a>00297         <span class="keywordflow">for</span> (uint32 i = 0; i &lt; num_samples; i++)
<a name="l00298"></a>00298         {
<a name="l00299"></a>00299                 samples[i][0] = (T(m_sample_x[i]) + m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>()) * inv;
<a name="l00300"></a>00300                 samples[i][1] = (T(m_sample_y[i]) + m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>()) * inv;
<a name="l00301"></a>00301         }
<a name="l00302"></a>00302 }
<a name="l00303"></a>00303 <span class="comment">// get a set of 3d stratified samples</span>
<a name="l00304"></a>00304 <span class="keyword">template</span> &lt;<span class="keyword">typename</span> T&gt;
<a name="l00305"></a><a class="code" href="structnih_1_1_sampler.html#ab533b105cb9adc3d64d9fe71015321ef">00305</a> <span class="keyword">inline</span> <span class="keywordtype">void</span> <a class="code" href="structnih_1_1_sampler.html#a393317f10a5ada969a41cf1f037bc900">Sampler::sample</a>(
<a name="l00306"></a>00306         <span class="keyword">const</span> uint32    num_samples,
<a name="l00307"></a>00307         <a class="code" href="structnih_1_1_vector_3_01_t_00_013_01_4.html">Vector&lt;T,3&gt;</a>*    samples)
<a name="l00308"></a>00308 {
<a name="l00309"></a>00309         m_sample_x.resize( num_samples );
<a name="l00310"></a>00310 
<a name="l00311"></a>00311         <span class="keyword">const</span> T inv = T(1.0) / T(num_samples);
<a name="l00312"></a>00312         <span class="keywordflow">for</span> (<span class="keywordtype">int</span> j = 0; j &lt; 3; j++)
<a name="l00313"></a>00313         {
<a name="l00314"></a>00314                 <span class="keywordflow">for</span> (uint32 i = 0; i &lt; num_samples; i++)
<a name="l00315"></a>00315                         m_sample_x[i] = i;
<a name="l00316"></a>00316 
<a name="l00317"></a>00317                 <span class="keywordflow">for</span> (uint32 i = 0; i &lt; num_samples; i++)
<a name="l00318"></a>00318                 {
<a name="l00319"></a>00319                         <span class="keyword">const</span> <span class="keywordtype">float</span> r = m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>();
<a name="l00320"></a>00320                         <span class="keyword">const</span> uint32 k = <a class="code" href="group__vectors.html#ga5809911d15c32de18955c59865379695">std::min</a>( uint32(<span class="keywordtype">float</span>(r) * (num_samples - i)) + i, num_samples-1u );
<a name="l00321"></a>00321                         std::swap( m_sample_x[i], m_sample_x[k] );
<a name="l00322"></a>00322                 }
<a name="l00323"></a>00323                 <span class="keywordflow">for</span> (uint32 i = 0; i &lt; num_samples; i++)
<a name="l00324"></a>00324                         samples[i][j] = (T(m_sample_x[i]) + m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>()) * inv;
<a name="l00325"></a>00325         }
<a name="l00326"></a>00326 }
<a name="l00327"></a>00327 <span class="comment">// get a set of 4d stratified samples</span>
<a name="l00328"></a>00328 <span class="keyword">template</span> &lt;<span class="keyword">typename</span> T&gt;
<a name="l00329"></a><a class="code" href="structnih_1_1_sampler.html#aaf4d230e452992719e6c17d5224ae2b4">00329</a> <span class="keyword">inline</span> <span class="keywordtype">void</span> <a class="code" href="structnih_1_1_sampler.html#a393317f10a5ada969a41cf1f037bc900">Sampler::sample</a>(
<a name="l00330"></a>00330         <span class="keyword">const</span> uint32    num_samples,
<a name="l00331"></a>00331         <a class="code" href="structnih_1_1_vector_3_01_t_00_014_01_4.html">Vector&lt;T,4&gt;</a>*    samples)
<a name="l00332"></a>00332 {
<a name="l00333"></a>00333         m_sample_x.resize( num_samples );
<a name="l00334"></a>00334 
<a name="l00335"></a>00335         <span class="keyword">const</span> T inv = T(1.0) / T(num_samples);
<a name="l00336"></a>00336         <span class="keywordflow">for</span> (<span class="keywordtype">int</span> j = 0; j &lt; 4; j++)
<a name="l00337"></a>00337         {
<a name="l00338"></a>00338                 <span class="keywordflow">for</span> (uint32 i = 0; i &lt; num_samples; i++)
<a name="l00339"></a>00339                         m_sample_x[i] = i;
<a name="l00340"></a>00340 
<a name="l00341"></a>00341                 <span class="keywordflow">for</span> (uint32 i = 0; i &lt; num_samples; i++)
<a name="l00342"></a>00342                 {
<a name="l00343"></a>00343                         <span class="keyword">const</span> <span class="keywordtype">float</span> r = m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>();
<a name="l00344"></a>00344                         <span class="keyword">const</span> uint32 k = <a class="code" href="group__vectors.html#ga5809911d15c32de18955c59865379695">std::min</a>( uint32(<span class="keywordtype">float</span>(r) * (num_samples - i)) + i, num_samples-1u );
<a name="l00345"></a>00345                         std::swap( m_sample_x[i], m_sample_x[k] );
<a name="l00346"></a>00346                 }
<a name="l00347"></a>00347                 <span class="keywordflow">for</span> (uint32 i = 0; i &lt; num_samples; i++)
<a name="l00348"></a>00348                         samples[i][j] = (T(m_sample_x[i]) + m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>()) * inv;
<a name="l00349"></a>00349         }
<a name="l00350"></a>00350 }
<a name="l00351"></a>00351 
<a name="l00353"></a>00353 <span class="keyword">template</span> &lt;<span class="keyword">typename</span> Image_type&gt;
<a name="l00354"></a><a class="code" href="structnih_1_1_sampler.html#ae4d59f4b95488b3b8d6c7559ec1bb6ef">00354</a> <span class="keywordtype">void</span> <a class="code" href="structnih_1_1_sampler.html#a393317f10a5ada969a41cf1f037bc900">Sampler::sample</a>(
<a name="l00355"></a>00355         <span class="keyword">const</span> uint32    num_samples,
<a name="l00356"></a>00356         <span class="keyword">const</span> uint32    num_dims,
<a name="l00357"></a>00357         Image_type&amp;             samples)
<a name="l00358"></a>00358 {
<a name="l00359"></a>00359         m_sample_x.resize( num_samples );
<a name="l00360"></a>00360 
<a name="l00361"></a>00361         <span class="keyword">typedef</span> <span class="keyword">typename</span> Image_type::Field_type T;
<a name="l00362"></a>00362 
<a name="l00363"></a>00363         <span class="keyword">const</span> T inv = T(1.0) / T(num_samples);
<a name="l00364"></a>00364         <span class="keywordflow">for</span> (uint32 j = 0; j &lt; num_dims; j++)
<a name="l00365"></a>00365         {
<a name="l00366"></a>00366                 <span class="keywordflow">for</span> (uint32 i = 0; i &lt; num_samples; i++)
<a name="l00367"></a>00367                         m_sample_x[i] = i;
<a name="l00368"></a>00368 
<a name="l00369"></a>00369                 <span class="keywordflow">for</span> (uint32 i = 0; i &lt; num_samples; i++)
<a name="l00370"></a>00370                 {
<a name="l00371"></a>00371                         <span class="keyword">const</span> <span class="keywordtype">float</span> r = m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>();
<a name="l00372"></a>00372                         <span class="keyword">const</span> uint32 k = <a class="code" href="group__vectors.html#ga5809911d15c32de18955c59865379695">std::min</a>( uint32(<span class="keywordtype">float</span>(r) * (num_samples - i)) + i, num_samples-1u );
<a name="l00373"></a>00373                         std::swap( m_sample_x[i], m_sample_x[k] );
<a name="l00374"></a>00374                 }
<a name="l00375"></a>00375                 <span class="keywordflow">for</span> (uint32 i = 0; i &lt; num_samples; i++)
<a name="l00376"></a>00376                         samples[i][j] = (T(m_sample_x[i]) + m_random.<a class="code" href="classnih_1_1_random.html#a5ae3693b17aa9d42645fc669181843f5" title="return a random [0,1) number">next</a>()) * inv;
<a name="l00377"></a>00377         }
<a name="l00378"></a>00378 }
<a name="l00379"></a>00379 
<a name="l00380"></a>00380 <span class="comment">// sample a cdf</span>
<a name="l00381"></a><a class="code" href="group__sampling.html#ga7f85d8d007bbaa744e558171b0064b8e">00381</a> <span class="keyword">inline</span> uint32 <a class="code" href="group__sampling.html#ga7f85d8d007bbaa744e558171b0064b8e">sample_cdf</a>(
<a name="l00382"></a>00382         <span class="keyword">const</span> <span class="keywordtype">float</span>                                     x,
<a name="l00383"></a>00383         <span class="keyword">const</span> std::vector&lt;float&gt;&amp;       cdf,
<a name="l00384"></a>00384         <span class="keywordtype">float</span>&amp;                                          pdf)
<a name="l00385"></a>00385 {
<a name="l00386"></a>00386 <span class="comment">//      const uint32 index = std::min( uint32( std::lower_bound( &amp;cdf[0], &amp;cdf[0] + cdf.size(), x ) - &amp;cdf[0] ), uint32(cdf.size()-1u) );</span>
<a name="l00387"></a>00387 <span class="comment">//      pdf = index == 0 ? cdf[0] : cdf[index] - cdf[index-1];</span>
<a name="l00388"></a>00388 <span class="comment">//      return index;</span>
<a name="l00389"></a>00389         uint32 index = <a class="code" href="group__vectors.html#ga5809911d15c32de18955c59865379695">std::min</a>( uint32( std::lower_bound( &amp;cdf[0], &amp;cdf[0] + cdf.size(), x ) - &amp;cdf[0] ), uint32(cdf.size()-1u) );
<a name="l00390"></a>00390     <span class="keywordflow">do</span>
<a name="l00391"></a>00391     {
<a name="l00392"></a>00392         pdf = index == 0 ? cdf[0] : cdf[index] - cdf[index-1];
<a name="l00393"></a>00393         <span class="keywordflow">if</span> (pdf &gt; 0.0f)
<a name="l00394"></a>00394             <span class="keywordflow">break</span>;
<a name="l00395"></a>00395     }
<a name="l00396"></a>00396     <span class="keywordflow">while</span>(++index &lt; cdf.size());
<a name="l00397"></a>00397 
<a name="l00398"></a>00398     <span class="keywordflow">return</span> index;
<a name="l00399"></a>00399 }
<a name="l00400"></a>00400 <span class="comment">// sample a cdf</span>
<a name="l00401"></a>00401 <span class="keyword">inline</span> uint32 <a class="code" href="group__sampling.html#ga7f85d8d007bbaa744e558171b0064b8e">sample_cdf</a>(
<a name="l00402"></a>00402         <span class="keyword">const</span> <span class="keywordtype">double</span>                            x,
<a name="l00403"></a>00403         <span class="keyword">const</span> std::vector&lt;double&gt;&amp;      cdf,
<a name="l00404"></a>00404         <span class="keywordtype">double</span>&amp;                                         pdf)
<a name="l00405"></a>00405 {
<a name="l00406"></a>00406 <span class="comment">//      const uint32 index = std::min( uint32( std::lower_bound( &amp;cdf[0], &amp;cdf[0] + cdf.size(), x ) - &amp;cdf[0] ), uint32(cdf.size()-1u) );</span>
<a name="l00407"></a>00407 <span class="comment">//      pdf = index == 0 ? cdf[0] : cdf[index] - cdf[index-1];</span>
<a name="l00408"></a>00408 <span class="comment">//      return index;</span>
<a name="l00409"></a>00409         uint32 index = <a class="code" href="group__vectors.html#ga5809911d15c32de18955c59865379695">std::min</a>( uint32( std::lower_bound( &amp;cdf[0], &amp;cdf[0] + cdf.size(), x ) - &amp;cdf[0] ), uint32(cdf.size()-1u) );
<a name="l00410"></a>00410     <span class="keywordflow">do</span>
<a name="l00411"></a>00411     {
<a name="l00412"></a>00412         pdf = index == 0 ? cdf[0] : cdf[index] - cdf[index-1];
<a name="l00413"></a>00413         <span class="keywordflow">if</span> (pdf &gt; 0.0f)
<a name="l00414"></a>00414             <span class="keywordflow">break</span>;
<a name="l00415"></a>00415     }
<a name="l00416"></a>00416     <span class="keywordflow">while</span>(++index &lt; cdf.size());
<a name="l00417"></a>00417 
<a name="l00418"></a>00418     <span class="keywordflow">return</span> index;
<a name="l00419"></a>00419 }
<a name="l00420"></a>00420 <span class="comment">// sample a cdf</span>
<a name="l00421"></a><a class="code" href="group__sampling.html#gae3dbf9f72ee99070878574ef9543785e">00421</a> <span class="keyword">inline</span> uint32 <a class="code" href="group__sampling.html#ga7f85d8d007bbaa744e558171b0064b8e">sample_cdf</a>(
<a name="l00422"></a>00422         <span class="keyword">const</span> <span class="keywordtype">float</span>                                     x,
<a name="l00423"></a>00423         <span class="keyword">const</span> uint32                            n,
<a name="l00424"></a>00424         <span class="keyword">const</span> <span class="keywordtype">float</span>*                            cdf,
<a name="l00425"></a>00425         <span class="keywordtype">float</span>&amp;                                          pdf)
<a name="l00426"></a>00426 {
<a name="l00427"></a>00427         <span class="keyword">const</span> uint32 index = <a class="code" href="group__vectors.html#ga5809911d15c32de18955c59865379695">std::min</a>( uint32( std::lower_bound( &amp;cdf[0], &amp;cdf[0] + n, x ) - &amp;cdf[0] ), uint32(n-1u) );
<a name="l00428"></a>00428         pdf = index == 0 ? cdf[0] : cdf[index] - cdf[index-1];
<a name="l00429"></a>00429         <span class="keywordflow">return</span> index;
<a name="l00430"></a>00430 }
<a name="l00431"></a>00431 
<a name="l00432"></a>00432 <span class="comment">// sample a cdf</span>
<a name="l00433"></a><a class="code" href="group__sampling.html#ga2ba33066ab272bd8b90be1046198a124">00433</a> <span class="keyword">inline</span> <span class="keywordtype">float</span> <a class="code" href="group__sampling.html#ga2ba33066ab272bd8b90be1046198a124">sample_cdf_cont</a>(
<a name="l00434"></a>00434         <span class="keyword">const</span> <span class="keywordtype">float</span>                                     x,
<a name="l00435"></a>00435         <span class="keyword">const</span> std::vector&lt;float&gt;&amp;       cdf,
<a name="l00436"></a>00436         <span class="keywordtype">float</span>&amp;                                          pdf)
<a name="l00437"></a>00437 {
<a name="l00438"></a>00438         <span class="keyword">const</span> uint32 index = <a class="code" href="group__vectors.html#ga5809911d15c32de18955c59865379695">std::min</a>( uint32( std::lower_bound( &amp;cdf[0], &amp;cdf[0] + cdf.size(), x ) - &amp;cdf[0] ), uint32(cdf.size()-1u) );
<a name="l00439"></a>00439         <span class="keyword">const</span> <span class="keywordtype">float</span> prev_cdf = index &gt; 0 ? cdf[index-1] : 0.0f; 
<a name="l00440"></a>00440         <span class="keyword">const</span> <span class="keywordtype">float</span> rem = (x - prev_cdf) / (cdf[index] - prev_cdf);
<a name="l00441"></a>00441         pdf = (cdf[index] - prev_cdf) * <span class="keywordtype">float</span>(cdf.size());
<a name="l00442"></a>00442         <span class="keywordflow">return</span> (<span class="keywordtype">float</span>(index) + rem) / <span class="keywordtype">float</span>(cdf.size());
<a name="l00443"></a>00443 }
<a name="l00444"></a>00444 
<a name="l00445"></a>00445 } <span class="comment">// namespace nih</span>
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